Expression Vector Signal Peptide Optimization for Protein Secretion
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current methods for large-scale protein production in biotechnology face challenges in achieving high yields, particularly in the secretion of heterologous proteins from host cells, due to inefficiencies in signal peptide selection and export processes during fermentation.
Innovation Solution
An expression vector is developed that includes a promoter sequence and a nucleic acid sequence coding for a protein with a signal peptide, where the signal peptide has an amino acid sequence at least 80% identical to a specified sequence, enhancing the secretion of proteins such as proteases, amylases, and lipases from host cells.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Productivity
If conventional signal peptides are used for protein secretion, then host cells can be cultivated in fermenters, but the secretion efficiency and product yield remain insufficient
Solution Approach 1:
The patent modifies the amino acid sequence of the signal peptide by introducing specific mutations (e.g., changing certain residues to improve hydrophobicity or charge distribution) to enhance its recognition and processing by the host cell's secretion machinery, thereby improving both secretion efficiency and product yield
Solution Approach 2:
The patent identifies and copies successful signal peptide sequences from native Bacillus proteins that are known to be efficiently secreted, and uses these copied sequences to fuse with heterologous proteins to achieve improved secretion performance
2Ease of manufacture
If heterologous proteins are expressed in host cells, then protein production can be achieved, but complex cell disruption is required for intracellular production
Solution Approach 1:
The patent uses a signal peptide as an intermediary element that directs the heterologous protein to the secretion pathway, acting as a mediator between the protein and the host cell's export machinery, thereby enabling extracellular production without complex cell disruption
Solution Approach 2:
The patent divides the protein structure into two functional segments: the signal peptide sequence responsible for secretion targeting and the heterologous protein sequence responsible for the desired function, allowing independent optimization of each component
3Reliability
If signal peptide libraries are screened to improve secretion, then export efficiency can be enhanced, but not every signal peptide causes sufficient export under fermentation conditions
Solution Approach 1:
The patent performs preliminary computational analysis and prediction of signal peptide properties (such as hydrophobicity, charge, and sequence motifs) before experimental testing, allowing selection of the most promising candidates and reducing the complexity of the screening process
Data Source
Figure 1A~1B
Figure 2
Figure 3
AI summary
The secretion of a protein from a host cell is to be improved in order to increase the protein product yield in a fermentation. This is achieved by an expression vector comprising a) a promoter sequence and b) a nucleic acid sequence encoding a protein, wherein the protein comprises a signal peptide and a further amino acid sequence, and the signal peptide comprises an amino acid sequence that is at least 80% identical to the amino acid sequence specified in SEQ ID NO. 2, or at least 80% identical to the amino acid sequence specified in SEQ ID NO. 4, or at least 80% identical to the amino acid sequence specified in SEQ ID NO. 6, or the signal peptide comprises an amino acid sequence that is structurally homologous to at least one of these sequences.